1. Field of the Invention
The present invention relates to an isolator.
2. Description of the Related Art
In an isolator used for work of handling a living-organism-derived material, such as cell culture, it is necessary to provide a dust-free/aseptic environment to the highest degree possible (hereinafter, referred to as aseptic environment) inside a working chamber or a pass box for bringing equipment necessary for the work and the like, in order to prevent intrusion of substances other than those necessary for the work. Hereinafter, a process of killing microorganisms, etc., to realize an aseptic environment is referred to as decontamination, and it is assumed that such a decontamination process includes processes of so-called sterilization, decolonization, and disinfection.
In a sterilizing liquid vaporizing device disclosed in Japanese Laid-Open Patent Publication No. 2003-339829, for example, heated compressed air and hydrogen peroxide solution are mixed and atomized by an atomizer, using hydrogen peroxide as decontamination material which is used for decontamination process, thereby producing hydrogen peroxide gas.
As such, decontaminating gas such as the hydrogen peroxide gas containing decontamination material is produced and supplied into a chamber to be decontaminated, such as a working chamber or a pass box, thereby being able to perform a decontamination process.
Each of an inlet and an outlet of the working chamber or the pass box in the isolator are provided with an air filter such as a HEPA (High Efficiency Particulate Air) filter and a ULPA (Ultra Low Penetration Air) filter, in order to remove impurities, such as dust, contained in gas to be taken in and discharged. However, depending on the combination of the decontaminating gas and the air filter to be used, as in a case where the hydrogen peroxide gas is used as the decontaminating gas and the HEPA filter is used as the air filter, for example, the air filter may have a property of having the decontaminating gas adsorbed thereon easily.
Thus, if the decontaminating gas is supplied from the inlet of the working chamber or the pass box, the decontaminating gas is adsorbed by the air filter, which leads to necessity for supplying more than a necessary amount of the decontaminating gas in expectation of an amount thereof to be absorbed, when decontaminating the working chamber or the pass box, resulting in inefficiency. On the other hand, if the decontaminating gas is supplied to the working chamber or the pass box without an air filter, it is not possible to sufficiently decontaminate the air filter (intake filter) of the inlet.